The systematic position of the Coeciliae has been, and is still, a controversial matter. The Sarasins took up Cope's suggestion, that their nearest allies are the Urodela, especially _Amphiuma_, and they went so far as to look upon _Amphiuma_ as a neotenic form of the "Coecilioidea," which they divided into Amphiumidae and Coeciliidae; the Coecilioidea and Salamandroidea forming the two sub-orders of the Urodela. They based this startling conclusion chiefly upon remarkable resemblances between _Amphiuma_ and _Ichthyophis_, namely, (1) the mode of laying the eggs on land and coiling themselves around them; (2) the existence of remnants of a tentacular apparatus in _Amphiuma_; (3) Cope's statement that _Amphiuma_ alone among the Urodela possesses an ethmoid like the Coeciliae. This latter point is, however, erroneous; it has since been shown by Davison[41] that _Amphiuma_ possesses no ethmoid bone, but that, instead of it, descending plates of the frontals join below the premaxilla and function as a nasal septum, with a canal for the olfactory nerves. We look upon the Apoda with more reason as creatures which of all the Lissamphibia have retained most Stegocephalous characters and at the same time form a highly specialised group equivalent to the Urodela and the Anura. The following are Stegocephalous inheritances peculiar to the Apoda in opposition to the other recent Amphibia: retention of cutaneous scales with calcareous incrustations, greatly resembling the scales of the Carboniferous Microsauri; occasional retention of post-frontal and lateral nasal or lacrymal bones, and of a second row of teeth in the mandible. To these may be added the presence of epiotic bones, and the primitive character of the branchial arches. The loss of all these characters would turn the present Apoda into limbless Urodela, but this assumption does not justify their inclusion in this Order. The possible homology of the tentacular apparatus has been discussed elsewhere, p. 45. {89}Fossil Apoda are not known; their subterranean life does not favour preservation. [Illustration: FIG. 14.–Map showing the distribution of the Coeciliae or Amphibia Apoda.] Only family, COECILIIDAE. About forty species are known. These have been placed in seventeen genera, mostly on comparatively slight grounds, and several of these genera are probably unnatural, the distinctive characters having undoubtedly been developed independently in various countries. We have to remember that the recent species are the remainder of a formerly much more numerous group; it is also likely that more will be discovered in the tropical forests of South America and Sumatra. Boulenger[42] has distinguished them as follows:–